The present invention is directed to a wear plate assembly for the saddle of a railcar truck, and in particular to a wear plate assembly having a first friction surface formed from a first material having a first coefficient of friction and a second friction surface formed from a second material having a second coefficient of friction.
Railroad car trucks include side frames that are resiliently supported at each end by a saddle and a plurality of resilient springs that extend between the saddle and the side frame. The saddle is rotatably mounted to a wheel set of the truck. In order to dampen vertical movement between the side frame and the saddle, a friction wedge is resiliently biased into engagement with a vertical wear plate of the saddle and with the side frame. When the railcar is at tare weight, or unloaded, the springs that support the side frame are extended and the friction wedge will engage the upper portion of the wear plate that is attached to the saddle. When the railcar is at fully laden weight, carrying a full load of goods or material to be transported, the springs supporting the side frame will be compressed and the friction wedge will engage a lower portion of the wear plate that is attached to the saddle.
A wear plate assembly adapted to engage a friction wedge of a railroad car truck. The wear plate assembly includes a base member including a first wear member and a mounting member having a recess. The first wear member includes a front friction surface adapted to engage the friction wedge. The mounting member is located adjacent to the first wear member. The wear plate assembly includes a second wear member having a front friction surface adapted to engage the friction wedge. The second wear member is adapted to be disposed within the recess of the mounting member and to be attached to the mounting member. The front friction surface of the second wear member is adapted to be located generally coplanar with the front friction surface of the first wear member. The first wear member is formed from a first material such as steel and the second wear member is formed from a second material, which is different than the first material, such as cast iron.